1. Field of the Invention
The present invention relates to a B-pillar to a rocker panel joint for vehicles and a method of assembling a tubular B-pillar to a rocker panel assembly.
2. Background Art
Vehicle bodies generally include a B-pillar that is defined as the pillar located behind a front seat door that extends between a rocker panel of the vehicle and a roof. Conventional B-pillars are manufactured by assembling stamped panels that are welded together with spot welds formed by resistance welding equipment.
It has been proposed to form body framing components by hydro-forming tubular members to provide stronger and more durable body framing members. Hydro-formed components provide stronger structural support members that are lighter weight. However, joining a tubular B-pillar with a stamped body component presents challenges compared to joining sheet metal components together because the closed section of the tubular members makes it difficult to weld using resistance welding equipment.
The B-pillar must be joined to both the roof joint and the rocker joint. The B-pillar to rocker joint is critical for crash safety and noise, vibration and harshness (NVH) performance. If the B-pillar to rocker joint is not sufficiently robust, the load carrying capacity of the B-pillar for crash safety will not be fully utilized. Any weakness in the B-pillar to rocker joint may also downgrade the vehicle's torsion and bending stiffness.
Hydro-formed B-pillars having a tubular cross-section do not normally have flanges that may be spot welded to a stamped rocker panel assembly and the outer panel of the body. In addition, the contact area between a hydro-formed tubular member and a stamped rocker assembly is normally smaller because in the hydro-forming process a constant periphery of the tube must be maintained.
These and other challenges are addressed by Applicants' invention as summarized below: